Endoscopic biopsy forceps jaws and instruments incorporating same

ABSTRACT

Endoscopic biopsy forceps jaws having an outer edge which may be generally U-shaped, circular, or oblate circular are disclosed with teeth which extend completely around the outer edge. The teeth may take any of several arrangements. In a first arrangement, the teeth and valleys are formed with two substantially rectangular surfaces which meet at substantially horizontal vertex and nadir lines. In a second arrangement, each tooth has a vertex or peak located upward and inward from the outer edge, and is defined by a substantially triangular inner surface, a substantially quadrilateral base, and a surface which extends outward and downward from the vertex of the triangular surface to the outer edge of the jaw. Valleys between the teeth have two inclined surfaces which intersect along a line which extends inward and downward from the outer edge of the jaw. In a third arrangement, the peak of each tooth is defined by the vertex of a pyramid having four faces and valleys between these teeth have three substantially flat surfaces which intersect at a vertex which lies downward and inward from the outer edge of the jaw. Alternate embodiments of all arrangements include providing a lip around the outer portion of the outer edge so that the teeth and valleys are spaced farther in from the outer surface of the jaw cup.

This application is a continuation-in-part of co-owned application Ser.No. 08/177,536 filed Jan. 5, 1994, now U.S. Patent No. 5,394,885 andco-owned Ser. No. 08/265,217 filed Jun. 24, 1994, now U.S. Pat. No.5,482,054 which in turn is a continuation of now abandoned co-owned Ser.No. 08/016,595 filed Feb. 11, 1993 now abandoned. This application isalso a continuation-in-part of co-owned application Ser. No. 07/837,046filed Feb. 18, 1992, now U.S. Pat. No. 5,507,296 which in turn is acontinuation of co-owned Ser. No. 07/521,766 filed May 10, 1990, nowU.S. Pat. No. 5,133,727.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to endoscopic biopsy forceps devices. Inparticular, the invention relates to biopsy forceps jaws having radiallyinclined teeth and biopsy forceps jaws having teeth which extendcompletely around the outer edge of a biopsy forceps jaw cup.

2. State of the Art

Endoscopic biopsy forceps are used for taking tissue samples from thehuman body for analysis. These forceps typically have a pair of cuppedjaws attached to the distal end of a long flexible coil, the proximalend of which is attached to actuating means which opens and closes thejaws when the actuating means is manipulated by the practitioner. Theendoscopic biopsy procedure is accomplished through an endoscope whichis inserted into a body and guided by manipulation to the biopsy site.The endoscope typically includes a long narrow flexible tube carryingdistal optical means and having a narrow lumen for receiving the biopsyforceps. The practitioner guides the endoscope to the biopsy site usingthe optical means and inserts the forceps, with jaws closed, through thelumen of the endoscope to the biopsy site. While viewing the biopsy sitethrough the optical means of the endoscope, the practitioner opens theforceps jaws and carefully guides the jaws around a tissue to besampled. When the jaws are in the correct position, the practitionermanipulates the actuating means and closes the jaws on the tissue to besampled. The cupped jaws grip the tissue and enclose a sample of thetissue in the space between the cupped jaws. The forceps are thenwithdrawn from the lumen of the endoscope while the jaws are kept shut,with the sample captured in the space between the cupped jaws typicallytorn away from the tissue at the biopsy site.

The endoscopic biopsy procedure poses several challenges to the designand manufacture of biopsy forceps and particularly biopsy forceps jaws.The jaws must be small enough to fit through the narrow lumen of theendoscope, yet strong enough and sharp enough to cut and/or tear tissue.An early example of an endoscopic biopsy forceps is shown in U.S. Pat.No. 3,895,636 to Schmidt. The forceps in Schmidt include a pair ofcupped toothless jaws with sharpened opposed edges intended to cutthrough tissue being sampled. Due to the miniature size of the jaws,however, it is difficult to sharpen the edges to a very high degree.Consequently, it is necessary to apply great force to the jaws in orderto sever the tissue being sampled. In practice, sufficient force tosever the tissue is rarely achieved. Thus, either the jaws effect aclamping action which permits the tissue to be torn away from the biopsysite, or the jaws simply slip off the tissue without cutting or tearingit.

U.S. Pat. No. 4,880,015 to Nierman shows endoscopic biopsy forcepshaving opposed rectangularly cupped jaws with teeth on their paralleledges. When the jaws close, opposed teeth interleave providing aslightly better gripping ability than the jaws disclosed by Schmidt.However, the rectangular configuration of the jaws and the absence ofteeth at the distal end of the jaws limits their functionality.Additionally, with these jaws and other toothed jaws, the teeth often donot align properly and prevent the jaws from closing completely whichadds to the inefficiency of cutting and/or tearing. Similarly, themisalignment of the opposed teeth sometimes causes the jaws to lock inthe closed position.

Co-owned U.S. Pat. No. 5,228,451 to Bales et al., the completedisclosure of which is hereby incorporated by reference herein,discloses endoscopic biopsy forceps having a pair of opposed jaws withteeth which extend along the entire U-shaped outer edge of each jaw. Theteeth are offset by one-half pitch relative to the longitudinal centerline of the jaw so that the upper jaw and lower jaw can be made from thesame mold and still allow the teeth to align (interleave) when the jawsare closed. This arrangement of jaw teeth greatly improves the cuttingand/or gripping (tearing) action of the forceps. It is a perceivedproblem, however, that this arrangement of teeth may expose a roughouter surface even when the jaws are closed during their entry into andexit from the lumen of the endoscope. It is believed by some that theperceived rough outer surface of the closed jaws might cause damage orundue wear to the lumen of the endoscope.

Parent application, Ser. No. 08/177,436, discloses biopsy forceps jawswhere the cup of each jaw has a wall with an outer side portion having acup edge and an inner side portion in which teeth are formed. The teethare defined by peaks and valleys formed in the inner side portion of thewall of the cup such that the peaks of the teeth rise above the edge andthe valleys remain below the edge of the outer side portion of the cupwall. In order to form the teeth in the inner side portion of the wall,the radial thickness of the teeth is less than the radial thickness ofthe cup wall, thereby causing the radially outer surface of the teeth tobe spaced radially inward from the outer surface of the cup wall. Whenthe two opposed jaws close, the peaks of the teeth on one jaw enter thevalleys of the teeth on the other jaw and the edges of the cup walls ofthe two jaws touch. In the closed position, the teeth of the two jawsare enclosed by the cup walls and the outer surface of the closed jawsis smooth. The cups of the jaws are provided with the general shape ofan oblate hemisphere or a portion of an oblate hemisphere, and the teethare radially arranged around at least a portion of the periphery of thecup and are offset by one half pitch relative to the longitudinal centerline of the cup so that two opposed identical jaws will mate asdescribed in co-owned U.S. Pat. No. 5,228,451 to Bales et al. Inaddition, the radially outer surface of the peaks and the radially innersurface of the valleys are radially chamfered. Thus, as the radiallychamfered peaks of the teeth of one jaw enter the radially chamferedvalleys of the teeth of the other jaw, moving points of contact betweenthe outer edges of the peaks and the cup wall edge above the valleyscause a scissoring action when the jaws are near fully closed. Theradial chamfering also aids in preventing the jaws from jamming shouldthey become misaligned to a point where the peak of a tooth on one jawmight stop against the cup wall of a mating jaw.

Parent application, Ser. No. 08/265,217, discloses endoscopic biopsyforceps having selective bipolar cautery in which a variety of differenttypes of forceps jaws are shown including jaws having teeth which extendcompletely around an oblate circular outer edge of the jaw cup.

SUMMARY OF THE INVENTION

It is therefore an object of the invention to provide endoscopic biopsyforceps jaws, wherein each one of a mating pair of jaws are identical toeach other.

It is also an object of the invention to provide endoscopic biopsyforceps jaws which are self-aligning and which permit greater tolerancein the dimensions of the jaws during manufacture.

It is another object of the invention to provide toothed endoscopicbiopsy forceps jaws which present a smooth outer surface when closed.

It is an additional object of the invention to provide toothedendoscopic biopsy forceps jaws having superior cutting and/or tearingability.

A further object of the invention is to provide endoscopic biopsyforceps jaws having teeth which align to allow the jaws to closecompletely without locking.

Another object of the invention is to provide endoscopic biopsy forcepsjaws having teeth which are radially inclined.

An additional object of the invention is to provide endoscopic biopsyforceps jaws having teeth which are radially arranged around the outeredge of the jaw and offset by one half pitch relative to thelongitudinal center line of the jaw.

Yet another object of the invention is to provide endoscopic biopsyforceps jaws having teeth which extend completely around the outer edgeof the jaw.

It is even a further object of the invention to provide an endoscopicbiopsy forceps instrument which incorporates the jaws of the invention.

In accord with these objects which will be discussed in detail below,the endoscopic biopsy forceps jaws of the present invention aregenerally hemispherically shaped cups having an outer edge which may begenerally U-shaped, circular, or oblate circular with the distal portionof the edge being curved. In a preferred embodiment, a number of teethare arranged radially (circumferentially) along at least a portion ofthe outer edge including the curved distal portion. Pairs of adjacentteeth on each jaw may be said to define interposed valleys within whichteeth from the opposing jaw mesh. In order that a pair of cooperatingjaws may be made from a single mold, the teeth are offset by one halfpitch relative to the longitudinal center line of the jaw as describedin co-owned U.S. Pat. No. 5,228,451 to Bales et al.

According to one embodiment of the jaws, each tooth is defined by aportion of the outer edge, an inner triangular surface with a vertex, aninclined line running down from the vertex of the inner surface out to amidpoint of the portion of the outer edge, and two preferably straightside lines at the same height as the outer edge. The valleys betweenthese teeth are similarly defined by a portion of the outer edge betweentooth portions, an inner triangular opening with a nadir, an inclinedline running up from the nadir to a midpoint on the portion of the outeredge, and two side lines shared with adjacent teeth. In this embodiment,all of the teeth are thereby inclined upward and inward from the outeredge of the jaw cup, while the valleys are inclined inward and downwardfrom the outer edge of the jaw cup. When two cooperating jaws close, theteeth of one jaw enter the valleys of the other jaw. When closed, theouter surface of the jaws is substantially smooth and shows only as astraight line interface between the outer edges of the opposed jaws,while the inside surface of the jaws looks like triangular teeth meshingwith triangular valleys.

According to a second embodiment of the jaws, each tooth is a four facedpyramid with the peak of each tooth being defined by the vertex of thepyramid. The valleys between these teeth have three substantially flatsurfaces which intersect at a nadir which lies downward and inward fromthe outer edge of the jaw. All of the teeth are inclined inward andupward from the outer edge of the jaw cup and the valleys are inclinedinward and downward from the outer edge of the cup. When two cooperatingjaws close and the teeth of one jaw enter the valleys of the other jaw,the outer surface of the jaws is substantially smooth and shows only asa straight line interface between the outer edges of the opposed jaws,while the inside surface of the jaws looks like triangular teeth meshingwith triangular valleys.

Alternate embodiments of both the first and second embodiment of thejaws include providing a lip around the outer portion of the outer edgeso that the teeth and valleys are spaced farther in from the outersurface of the jaw cup. The lip may be sharp or dull. The tooth geometryof either the first or second embodiment can be utilized in jaw cupshaving an outer edge which is U-shaped, circular, or oblate circular.Where the jaw cups are circular or oblate circular, the teeth may bearranged so that they extend completely around the edge of the jaw.Further combinations and permutations of the features of the differentembodiments will be apparent from the detailed description below.

The present invention also provides an endoscopic biopsy forcepsinstrument which generally includes a flexible coil having a proximaland a distal end, at least one pull wire extending through the coil, anactuation handle coupled to the proximal ends of the coil and the pullwire(s), and a clevis coupled to the distal end of the coil. Each of theembodiments of the endoscopic biopsy forceps jaws is provided with aproximal tang having means for rotatably mounting to the clevis and ameans for coupling the tang to the distal end of a pull wire. Additionalobjects and advantages of the invention will become apparent to thoseskilled in the art upon reference to the detailed description taken inconjunction with the provided figures.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side elevation view, partially in cross-section of apreferred endoscopic biopsy forceps instrument according to theinvention;

FIG. 2 is an enlarged side elevation view of the distal end of thebiopsy forceps instrument of FIG. 1 with a first embodiment of biopsyforceps jaws according to the invention;

FIG. 3 is a top view of one of the jaws of FIG. 2;

FIGS. 3a-3c are partial perspective views of several teeth and valleysof the jaw of FIG. 3;

FIG. 3d is a broken side elevational view showing two teeth and onevalley of the jaw of FIG. 3 as viewed from inside the jaw;

FIG. 3e is a broken perspective view of portions of two biopsy forcepsjaws of the embodiment of FIG. 3 in the closed position;

FIG. 4 is a side elevation view of the jaw of FIG. 3;

FIG. 5 is a cross sectional view along line 5--5 of FIG. 3;

FIG. 6 is a broken side elevation view of a portion of the jaw of FIG.3;

FIG. 7 is a distal end view of the jaw of FIG. 4;

FIG. 8 is a partial sectional view along line 8--8 in FIG. 3;

FIG. 9 is a top view of an alternate first embodiment of a biopsyforceps jaw according to the invention;

FIG. 10 is a top view of a second embodiment of biopsy forceps jawsaccording to the invention;

FIG. 11 is a broken perspective view showing the tooth geometry of apair of biopsy forceps jaws according to the embodiment of FIG. 10viewed from outside the jaws;

FIG. 11a is a broken perspective view showing the biopsy forceps jaws ofFIG. 11 in the closed position viewed from outside the jaws;

FIG. 12 is a view similar to FIG. 11, but viewed from inside the jaws;

FIG. 12a is a broken perspective view showing the biopsy forceps jaws ofFIG. 12 in the closed position viewed from inside the jaws;

FIG. 13 is a top view of an alternate second embodiment of a biopsyforceps jaw according to the invention;

FIG. 14 is a top view of a third embodiment of a biopsy forceps jawaccording to the invention;

FIG. 15 is a side elevation view of the third embodiment of a biopsyforceps jaw according to the invention;

FIG. 16 is an end view of the third embodiment of a biopsy forceps jawaccording to the invention;

FIG. 17 is a top view of a first alternate third embodiment of theinvention;

FIG. 18 is a side elevation view of the first alternate third embodimentof the invention;

FIG. 19 is a top view of a second alternate third embodiment of theinvention;

FIG. 20 is a top view of a third alternate third embodiment of theinvention; and

FIG. 21 is a top view of a fourth alternate third embodiment of theinvention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring now to FIGS. 1 and 2, the preferred endoscopic biopsy forcepsinstrument 10 of the invention is shown with a distal end 12 having abiopsy jaw assembly 14, and a proximal end 16 having a handle 17, aspool 19 and a thumb ring 21. The biopsy jaw assembly 14 generallyincludes a clevis 18 and a pair of identical jaws 30. Each identical jaw30 has a distal toothed cup 32, a proximal tang 34, and a transversemounting bore 36. The jaws 30 are mounted on the clevis 18 by a pin 37which passes through their mounting bores 36. The proximal tang 34 ofeach jaw is provided with a pull wire coupling bore 31 and is therebycoupled to the distal end of a control member or pull wire 38 whichextends through a hollow member or coil 39. The proximal end of eachpull wire 38 is coupled to the spool 19 which is slidably attached tothe handle 17. The jaws are opened and closed by movement of the spool19 relative to the handle 17 as described more fully in co-owned U.S.Pat. No. 5,228,451 to Bales et al.

FIGS. 3, 3a-3e, and 4 through 8 show a first embodiment of the biopsyforceps jaws 30. In the first embodiment, the distal toothed cup 32 ofthe jaw 30 is an oblate hemispherical member having a generally U-shapedouter edge 33, a hollow interior 35, and an optional fenestration hole37 at the bottom of the hollow interior 35. Extending from the outeredge 33 are a number of teeth 40-51 which are separated by acorresponding number of valleys 40V-51V. As seen best in FIG. 3, thecurved distal end of the cup 32 is provided with teeth 43-48 and valleys43V-48V at least some of which are radially arranged about a point "R"as described more fully in co-owned U.S. Pat. No. 5,228,451 to Bales etal. Additionally, in the preferred embodiment, the teeth 40-42 and thevalleys 40V-42V on one side of the longitudinal centerline "CL" of thecup 32 are displaced by one half pitch from the teeth 49-51 and thevalleys 49V-51V on the other side of the centerline of the cup 32. Thisradial arrangement and half pitch displacement provides forself-alignment and the ability to use a single cast to make a pair ofidentical mating jaws as described in U.S. Pat. No. 5,228,451 to Baleset al. Since the teeth do not completely encircle the cup 32, partingline planes 40p and 51p are provided proximal of valley 40v and tooth51, respectively

According to the first embodiment of the invention, and as seen best inFIGS. 3a-3d, each tooth rises as it extends inward from the outer edge33 to a triangular face T on the inner surface 33a of the jaw cup 32.The base of each tooth can be described as a quadrilateral having sidesL1-L4. Side L1 is a portion of the outer edge 33 of the cup 32. Sides L2and L3 are imaginary lines which extend inward from the outer edge 33 atthe same elevation as the outer edge 33. Side L4 is an imaginary linewhich connects lines L2 and L3 and is the base of the triangular face T.A tooth edge E extends outward and downward from the vertex V of thetriangular face T to the midpoint of side L1. Those skilled in the artwill appreciate that the surfaces S1 and S2 formed between the edge Eand the sides L2 and L3 are relatively complex, but may be approximatelydescribed as trapezoidal planes which have been twisted to a peak V. Thetwisted trapezoidal plane may be understood by appreciating that thedistance between point P1 (intersection of L1 and L3) and point P2(intersection of L1 and E) is smaller than the distance between point P3(intersection of L3 and L4), and point V. Thus, if P1, P2, P3, and Vwere in the same plane, with lines L1 and L7 being parallel, they wouldform a trapezoid. However, while all of the points along lines L1, L2,and L3, including P1, P2, and P3 preferably lie in the same horizontalplane, point V lies in a different plane. Thus, the trapezoid istwisted.

To further define the surfaces S1 and S2, it should be appreciated thatin the preferred embodiment, lines L2, L3, and edge E (when projectedinto the horizontal plane) are all preferably parallel to each other;and the distance between E and L2 or L3 increases as the peak of thetooth rises. The surfaces S1 and S2, therefore, are not completelyplanar (flat). Depending on how the jaw cup is made, the geometricalconditions set forth above may be satisfied by surfaces S1 and S2 whichare concave, convex, or a combination of concave and convex. Moreover,the surfaces S1 and S2 may be formed from a series of faceted surfaceswhere each facet is a slightly twisted trapezoid. Each facet could alsobe formed as two planar triangles in order to facilitate machining. Thetwisted trapezoids may take either a convex or concave form, or mayalternate between convex or concave in order to form as flat a surfaceas possible. It should be appreciated that whether edge E is a straightline or a curved line will influence the surface geometry of surfaces S1and S2. Likewise, it will be appreciated that edge E does not have to bea discontinuity between surfaces S1 and S2, but may rather be a line ofhighest topology which artificially separates surfaces S1 and S2.

Interposed between each tooth is a valley which has a geometry forreceiving an opposed tooth. In particular, each valley descends from theouter edge 33 of the cup 32 to a triangular opening T0 in the innersurface 33a of the cup 32. The base of each valley can be described as aquadrilateral having sides L5, L2, L3, and L6. Side L5 is a portion ofthe outer edge 33 of the cup 32. Sides L2 and L3 are the imaginary linesdescribed above from teeth adjacent to the valley. Side L6 is animaginary line colinear with the imaginary lines L4 from adjacent teeth.A valley trough VT extends upward from the nadir N of triangular openingT0 to the midpoint of L5. The surfaces S3 and S4 formed between thevalley trough VT and the imaginary lines L2 and L3 have a geometry whichpreferably is the inverse of the geometry of the surfaces S1 and S2 onthe teeth. In this way, each valley will mesh with an opposing toothwithout any significant gap between mating surfaces. However, ifdesired, surfaces S3 and S4, rather than having an inverse geometry tothose of surfaces S1 and S2 can have an identical geometry thereto,particularly, if the geometry is generally concave. With such anarrangement, gaps would be generated between the teeth and valleys ofthe opposing jaws.

Those skilled in the art will appreciate that the imaginary line L2 neednot be a discontinuity between surfaces S1 and S4 and that these twosurfaces may be seen as a single continuous surface extending from anedge E to an adjacent valley trough VT. Such a continuous surface may beapproximately described as a twisted trapezoidal plane. The same is truefor line L3, and surfaces S2 and S3.

While the surface structure of the first embodiment of the invention issomewhat complex, it will be appreciated that the top view of the teethhas virtually the same appearance as the top view of the teeth of theparent application Ser. No. 08/265,217 which have two triangular facesand two rectangular faces (see also FIGS. 14-17, and 19 herein below).Moreover, as seen in FIG. 3e, when the jaws are closed, they present asmooth outer surface with a straight line interface between outer edges,while from the inside (see FIG. 3d), they present triangular teethmeshed with triangular valleys.

An alternate first embodiment of the biopsy forceps jaw is shown in FIG.9. The jaw 130 is substantially the same as the jaw 30 described above,except for the step or lip 133L which extends around outer periphery ofthe outer edge 133. Such a lip is described in more detail in parentapplication Ser. No. 08/177,536. The lip 133L may be sharp or dull. InFIG. 9 and the Figures which follow, similar numbers, increased byhundreds, are used to indicate similar features of the differentembodiments of the invention.

Turning now to FIGS. 10-12, a second embodiment of a biopsy forceps jaw230 is seen with a distal jaw cup 232, and a proximal tang 234 having aclevis mounting bore 236 and a pull wire coupling bore 231. The overallshape of the distal cup 232 is substantially the same as the jaw cup 32described above, having an interior hollow 235 with an optionalfenestration hole 237. A number of teeth 240-250 are arranged upward andinward from the outer edge 233 of the cup 232 and a number of valleys240V-250V are interposed between the teeth as seen best in FIG. 10. Theprimary difference between this embodiment and the first embodimentdescribed above is the geometry of the teeth 240-250. FIGS. 11 and 12illustrate a broken portion of two jaws 230 spaced apart from each otherin their engaging relationship. Here it will be appreciated that eachtooth, e.g., tooth 250, is formed as a pyramid having four triangularfaces T1-T4 which intersect at a vertex T5. The vertex T5 is locatedupward and radially inward from the outer edge 233 of the cup 232.Similarly, each valley, e.g., valley 240V, is formed by three triangularsurfaces V1-V3 which intersect at a nadir V4. The nadir V4 is locateddownward and radially inward from the outer edge 233 of the cup 232. Itwill also be appreciated that two of the surfaces (V2 and V3) of eachvalley are contiguous with respective T2 and T4 faces of adjacent teeth.The outer edge V5 of each valley appears as a straight line betweenadjacent teeth, and this edge V5 may be either sharp or dull.

The inner face T3 of each tooth is preferably substantially parallel toa plane tangent to the outer edge 233 of the cup, but it will beappreciated that face T3 could be angled either inward or outwardrelative to the interior of the cup. As seen in FIGS. 11a and 12a, whenthe jaws are closed, they present a smooth outer surface with a straightline interface between outer edges 233, while from the inside, theypresent triangular teeth meshed with triangular valleys.

An alternate second embodiment of the biopsy forceps jaw is shown inFIG. 13. The jaw 330 is substantially the same as the jaw 230 describedabove, except for the step or lip 333L which extends around outerperiphery of the outer edge 333. Such a lip is described in more detailin parent application Ser. No. 08/177,536. The lip 333L may be sharp ordull.

A third embodiment of the invention is shown in FIGS. 14 through 16. Inthe third embodiment, the endoscopic biopsy forceps jaw 430 has a distaljaw cup 432 and a proximal tang 434 with a clevis mounting bore 436 anda pull wire coupling bore 431. The overall shape of the distal cup 432is substantially the same as the jaw cups described above, having aninterior hollow 435. In this embodiment however, the outer edge 433 ofthe cup is not U-shaped, but is an oblate circle as seen best in FIG.14. A number of teeth 440-454 are arranged along the outer edge 433 ofthe cup 432 and a number of valleys 440V-454V are interposed between theteeth. In this embodiment of the invention, the teeth 440-454 encirclethe entire perimeter of the outer edge. The geometry of the teeth inthis embodiment is substantially the same as described in parentapplication Ser. No. 08/265,217, where the teeth and valleys are formedwith two substantially rectangular surfaces which meet at substantiallyhorizontal vertex and nadir lines. The significance of the thirdembodiment, therefore, is not the specific tooth geometry, but the factthat the teeth are arranged 360° around the cup. As with the otherembodiments discussed thus far, at least some of the teeth in thisembodiment are arranged radially, and the teeth on either side of thecup are preferably offset by one half pitch so that a pair of matingjaws may be made from a single mold.

A first alternate third embodiment of the invention is shown in FIGS. 17and 18. The jaw 530 shown in FIGS. 17 and 18 is substantially the sameas the jaw 430 described above except that the geometry of the teeth540-553 is that of the first embodiment of the invention. Thisembodiment of the invention, therefore, combines features of the oblatecircular outer edge of the third embodiment with the tooth geometry ofthe first embodiment.

A second alternate third embodiment is shown in FIG. 19 and issubstantially the same as the embodiment of FIGS. 17 and 18 except forthe lip 633L which surrounds the outer edge 633 of the cup 632 of thejaw 630.

A third alternate third embodiment of the invention is shown in FIG. 20.The jaw 730 shown in FIG. 20 is substantially the same as the jaw 430described above except that the geometry of the teeth 740-753 is that ofthe second embodiment of the invention. This embodiment of theinvention, therefore, combines features of the oblate circular outeredge of the third embodiment with the four faced pyramid tooth geometryof the second embodiment.

A fourth alternate third embodiment is shown in FIG. 21 and issubstantially the same as the embodiment of FIG. 20 except for the lip833L which surrounds the outer edge 833 of the cup 832 of the jaw 830.

There have been described and illustrated herein several embodiments ofan endoscopic biopsy forceps jaw cup. While particular embodiments ofthe invention have been described, it is not intended that the inventionbe limited thereto, as it is intended that the invention be as broad inscope as the art will allow and that the specification be read likewise.Thus, while particular tangs, clevis mounting means, and pull wirecoupling means have been disclosed, it will be appreciated that othertangs, clevis mounting means, and pull wire coupling means could beutilized. Also, while specific tooth geometries have been shown to placethe peak of each tooth radially inward from the outer edge of the jawcup, it will be recognized that other tooth geometries could be usedwith similar results obtained. Moreover, while particular configurationshave been disclosed in reference to a biopsy forceps deviceincorporating the jaws of the invention, it will be appreciated thatother configurations could be used as well. Furthermore, while the jawcups have been disclosed as having teeth which are offset by one halfpitch, it will be understood that many of the novel features of theinvention can be obtained with nonidentical jaw cups made from twoseparate molds. It will therefore be appreciated by those skilled in theart that yet other modifications could be made to the provided inventionwithout deviating from its spirit and scope as so claimed.

We claim:
 1. An endoscopic biopsy forceps jaw for use with an endoscopicbiopsy forceps instrument having a hollow member with a control memberextending therethrough, actuating means coupled to the proximal ends ofthe hollow member and control member for reciprocally moving the controlmember through the hollow member, and a pair of forceps jaws at leastone of said pair being said endoscopic biopsy forceps jaw, saidendoscopic biopsy forceps jaw comprising:a) a distal jaw cup having anouter edge and an interior hollow portion, said outer edge being one ofcircular and oblate circular; and b) a proximal coupling means forcoupling said distal jaw cup to at least one of the control member andthe hollow member of the biopsy forceps instrument such that the pair offorceps jaws will open and close with the reciprocally moving controlmember, whereinsaid distal jaw cup has a plurality of teeth which extendsubstantially 360° around said distal jaw cup.
 2. An endoscopic biopsyforceps jaw according to claim 1, wherein:at least some of said teethare radially arranged along said distal jaw cup.
 3. An endoscopic biopsyforceps jaw according to claim 2, wherein:said teeth include first teethon a first side of said distal jaw cup, and second teeth on a secondside of said distal jaw cup, said first teeth and said second teethbeing offset by one half pitch relative to each other.
 4. An endoscopicbiopsy forceps jaw according to claim 1, wherein:said outer edge has anouter lip, said teeth extending from said distal jaw cup from a locationinterior of said outer lip.
 5. An endoscopic biopsy forceps jawaccording to claim 4, wherein:said outer lip is unsharpened.
 6. Anendoscopic biopsy forceps jaw according to claim 4, wherein:said outerlip is sharpened.
 7. An endoscopic biopsy forceps jaw according to claim1, wherein:said plurality of teeth extend from said jaw cup, each toothhaving a vertex which is located upward and inward from said outer edge.8. An endoscopic biopsy forceps jaw according to claim 7, wherein:eachtooth has a substantially triangular inner surface with said vertexbeing a vertex of said substantially triangular inner surface and asurface which extends from said vertex outward and downward to saidouter edge.
 9. An endoscopic biopsy forceps jaw according to claim 7,wherein:said distal jaw cup has a plurality of tooth valleys interposedbetween said teeth, each tooth valley having a nadir which is locateddownward and inward from said outer edge.
 10. An endoscopic biopsyforceps jaw according to claim 9, wherein:each of said tooth valleys hastwo inclined surfaces which intersect along a line extending inward anddownward from said outer edge.
 11. An endoscopic biopsy forceps jawaccording to claim 9, wherein:each of said tooth valleys has threesubstantially triangular surfaces which intersect at a nadir pointlocated inward and downward from said outer edge.
 12. An endoscopicbiopsy forceps jaw according to claim 7, wherein:each of said teeth hasfour substantially triangular surfaces.
 13. An endoscopic biopsy forcepsjaw according to claim 7, wherein:said teeth are radially arranged alongsaid distal jaw cup.
 14. An endoscopic biopsy forceps jaw according toclaim 13, wherein:said teeth include first teeth on a first side of saiddistal jaw cup, and second teeth on a second side of said distal jawcup, said first teeth and said second teeth being offset by one halfpitch relative to each other.
 15. An endoscopic biopsy forceps jawaccording to claim 7, wherein:said jaw cup is substantially oblatehemispherical.
 16. An endoscopic biopsy forceps jaw according to claim15, wherein:said outer edge is substantially U-shaped.
 17. An endoscopicbiopsy forceps jaw according to claim 15, wherein:said outer edge issubstantially oblate circular.
 18. An endoscopic biopsy forceps jawaccording to claim 7, wherein:said outer edge has an outer lip, saidteeth extending from a location interior of said outer lip.
 19. Anendoscopic biopsy forceps jaw according to claim 18, wherein:said outerlip is unsharpened.
 20. An endoscopic biopsy forceps jaw according toclaim 18, wherein:said outer lip is sharpened.
 21. An endoscopic biopsyforceps instrument, comprising:a) a hollow member having a proximal anda distal end; b) a control member having a proximal and a distal end andextending through said hollow member; c) actuating means coupled to saidproximal ends of said hollow member and said control member forreciprocally moving said control member through said hollow member; andd) a pair of forceps jaws, whereineach of said forceps jaws has a distaljaw cup having an outer edge and an interior hollow portion, said outeredge being one of circular and oblate circular, a proximal couplingmeans for coupling said distal jaw cup to at least one of said controlmember and said hollow member such that the pair of forceps jaws willopen and close in response to reciprocally moving said control member,and said distal jaw cup has a plurality of teeth which extendsubstantially 360° around said distal jaw cup.
 22. An endoscopic biopsyforceps instrument according to claim 21, wherein:at least some of saidteeth are radially arranged along said distal jaw cup.